Marie Claude Ouimet, PhD, of the University of Sherbrooke in Longueuil, Canada, and colleagues conducted an 18-month longitudinal, naturalistic study involving 42 newly licensed 16-year-old drivers. The researchers assessed the relationship between cortisol response to stress and driving risk.

The researchers found that teenaged drivers with a higher cortisol response to a stress-inducing task at baseline had lower crash and near-crash (CNC) rates during their first 18 months of licensure (exponential of the regression coefficient, 0.93; 95% confidence interval [CI], 0.88–0.98) and faster decrease in CNC rates over time (exponential of the regression coefficient, 0.98; 95% CI, 0.96–0.99).

"In sum, while the results of [this] study do present an interesting new line of research, they do not suggest that we are close to developing a clinically useful biomarker-based diagnostic test nor a pharmaceutical therapy to reduce the risk for teen-driver crashes," write the authors of an accompanying editorial.